Rough idle 07 yukon 5.3

[Armstrong82]

I have an 07 yukon with the 5.3. It has always idled a little rough but is now it miss firing on cylinders 1 and 7 pretty much constant while idling. While driving it's either not miss firing at all or is at least not noticeable. I've done plugs and boots all the way around and coil packs on #1 and #7. It didn't change a thing. Still miss firing at idle. Could it be bad injectors or something more serious? What cylinders drop out when it goes to 4 cylinder mode and is it the same every time? Thanks in advance to anybody who can shed some light onto my ongoing struggles.

 

[992dr]

Fuel, air, spark is the route to go first.
1 4 6 7 are DOD cylinders.
Have you cleaned your tb? I just cleaned mine and was pleasantly surprised with the results.
If you know someone with a tech II scan tool that can take it out for a spin, they might be able to find where the misfire is coming from.
Good luck and let us know what happens